Poster abstracts
Poster number 19 submitted by Wenjun Sun
Histone H4 Tail Conformation in Nucleosomes Studied by Paramagnetic NMR
Wenjun Sun (Department of Chemistry and Biochemistry, The Ohio State University ), Nicole Gonzalez Salguero (Department of Chemistry and Biochemistry, The Ohio State University ), Matthew Shannon (Department of Chemistry and Biochemistry, The Ohio State University ), Mohamad Zandian (Department of Chemistry and Biochemistry, The Ohio State University ), Michael Poirier (Department of Physics, The Ohio State University ), Christopher Jaroniec (Department of Chemistry and Biochemistry, The Ohio State University )
Abstract:
The packaging of DNA into chromatin plays a critical role in genome function. The fundamental repeat unit of chromatin, the nucleosome, consists of ~147 bp DNA and a histone protein octamer containing two copies each of histones H2A. H2B, H3 and H4. Dynamically disordered H4 N-terminal tails are key components in chromatin regulation. Here we investigate the conformational ensemble of these H4 tail domains in nucleosomes by paramagnetic relaxation enhancement (PRE) solution NMR spectroscopy and recombinant nucleosomes reconstituted with 15N-enriched H4 and labeled with paramagnetic nitroxide spin label tags at multiple histone H3 sites located on the nucleosome surface. The experimental PRE data are interpreted in conjunction with MD simulations, which indicate that H4 tails engage in a fuzzy interaction with nucleosomal DNA.
Keywords: Nucleosome, NMR